CONWAY -- Missing teenager Abigail Hernandez's cell phone was last used at 6:30 p.m. on Wednesday, the day she disappeared after walking home from Kennett High School, officials said.

According to officials, the call was made in the vicinity of Cranmore Mountain Resort. Her cell phone "hasn't been used since," said Major Kevin Jordan of the NH Fish and Game Law Enforcement Division on Sunday.

In one of three cases on Saturday that warranted a call to the state Medical Examiner's office, trackers found a human skull with teeth during their search for the missing teen.

"We were actually looking for Abby, and were looking in the area of the cell phone band from the tower signal the last time her phone was activated," Jordan said.

As NH Fish and Game officers walked the grid in the vicinity of the cell tower phone signal, they discovered a skull with teeth that will be sent to the state lab on Monday and analyzed for DNA. Major Jordan said the skull might belong to a man from the area who has been missing in July 2006. Since no identification has yet been made, the missing man's family has not been notified.

During the last press briefing on Saturday evening at the Conway Police Department, Conway Police Chief Ed Wagner and Major Jordan said the search has yielded no substantial information about Abby's whereabouts, but the search is far from over.

Abby's mother, Zenya Hernandez made a tearful plea for Abby to come home, wished her happy birthday, and asked anyone who has noticed a change in her behavior or who knows anything to come forward.

Major Jordon first mentioned finding human remains, and a hiker fatality during the press conference. He said he didn't want the public to think, when they heard that a medical examiner had been called to the vicinity, that the search for Abby was over.

"What my concern was, in both instances, the 60-year-old hiker who died and the recovered bones, prompted calls to the medical examiner. I didn't want people who might have information (about Abby) to not call, thinking this has been resolved," he said.

On Sunday, five more teams from NH Fish and Game searched in the area of Kennett High School and near a local quarry. A press conference was set for 6 p.m. Sunday at the Conway police station.